Method of and apparatus for reducing the thickness of metals



K. SAXL METHOD OF AND APPARATUS FOR REDUCING THE THICKNESS 0F METALS 4 Sheets-Sheet 1 Filed Jan. 2, 1959 Sept. 10, 1963 K. SAXL 3,103,139

METHOD OF AND APPARATUS FOR REDUCING THE THICKNESS OF METALS Filed Jan. 2, 1959 4 Sheets-Sheet 2 Sept. 10, 1963 K. SAXL 3 103, 39

METHOD OF AND APPARATUS FOR REDUCING THE THICKNESS 0F METALS Filed Jan. 2, 1959 1 4 Sheets-Sheet 3 KA /n51. SAXL W Z, f B y 770/9/Vfk5 Sept. 10, 1963 K. SAXL 3,103,139

METHOD OF AND APPARATUS FOR REDUCING THE THICKNESS OF METALS Filed Jan. 2, 1959 4 Sheets-Sheet 4 IN VENTOR ATTORNEYS United States Patent 3,1tl3,139 METHQD OF AND APPARATUd FUR REDUCLJG THE THi'CKNESS 0F METALS Karel Saul, Sutton Coldiield, England, assignor to linperiai Chemical industries Limited, London, England, a corporation of Great Britain Filed .lan. 2, 1959, Ser. No. 734,524 Claims priority, application Great Britain den. 3, 1953 4 Claims. (U. 8tl4tl) This invention is concerned with a method of and apparatus for reducing the thickness of metals in slab, plate or strip form.

According to this invention, there is provided a method of reducing the thickness of metal in which the metal is progressively moved between a pair of freely-rotatable work-rolls which swing forwardly and backwardly in synchronism with each other in such manner that the metal is reduced in thickness between the work-rolls during swinging movement of the work-rolls in one direction but undergoes little or no reduction throughout swinging movement of the work-rolls in the other direction.

According to a feature of the invention as set forth in the preceding paragraph, the metal is fed continuously between the work-rolls, but it may, if desired, be fed intermittently during the time when the rolls are reducing the thickness of the metal.

Also according to this invention, there is provided apparatus for reducing the thickness of metal, comprising a pair of oppositely directed swingable arms, the free ends of which are adjacent, a freely-rotatable work-roll mounted on the free end of each arm, mechanical driving means operable so as to cause swinging of the arms back-weirdly and forwardly in synchronism with each other and a further driving means operable in synchrouism with the firstmentioned mechanical driving means to move the pivots on which the arms are mounted away from each other at some stage of the swinging movement of the arms and to move back towards each other at a later stage of the swinging movement.

According to a feature of the invention, there is also provided apparatus for reducing the thickness of metal comprising a pair of oppositely directed swingable arms, the free ends of which are adjacent, a freely-rotatable work-roll mounted on the free end of each arm, mechanical driving means operable so as to cause swinging of the arms backwardly and forwardly in synchronism with each other in the same plane.

The swin-gable anms move in synchronism in a pendulum-like manner, preferably at high speed, and because of this resemblance the arms will hereinafter be referred to as pendulums.

The method according to the invention may be applied to continuous or to very long lengths of metal in strip form or to shorter lengths of sheet or plate joined together end to end to form a long length.

Deformation of the metal occurs when the pendulums move in one direction, such direction preferably being opposite to the direction of movement of the metal. Thus, in one embodiment, the Wonk-rolls deform the metal when the pendulurns move in the direction opposite to the direction of movement of the strip and are lifted clear of the strip during the return stroke of the pendulums.

In a second embodiment, on the return stroke, the work-rolls remain in contact with the metal but do not reduce the thickness of the metal during the return stroke. Whether the rolls remain in contact or not depends on the amount of movement of the pendulums towards and away from the strip. In the preferred form of apparatus to be described in detail hereinafter, the means for regulating such movement is an eccentric, on which the pendulum is pivoted, which is rotated to raise or lower the pendulum. By choosing a suitable degree of eccentricity or by limiting the amount of rotation, the amount of up and down movement can be regulated.

During deformation of the strip, some distortion of the frame and other parts of the apparatus occurs. This distortion is hereinafter referred to as mill strain and the effect is to widen the gap between the work-rolls. When the pendulum-s reach the end of the deformation stroke the mill strain is relieved and the gap between the work-rolls is reduced. This variation of the gap under the deformation load produces some up and down movement which has to be allowed for, and by adjustment of the eccentric mechanism in conjunction with the amount of up and down movement of the pendulums due to mill strain, the Work-rolls, during the return stroke, can be made either to contact the strip without deformation or to rise clear of the strip.

Hard metals such as titanium, are preferably reduced whilst hot and for this purpose a furnace may be provided through which the strip passes before passing between the work-rolls.

In order to minimise deflection of the work-rolls whilst under load, freely-rotatable backing rolls may be provided.

An apparatus for reducing the thickness of metal in accordance with one embodiment of the invention is illustrated in the accompanying drawings of which:

FIGURE 1 is a schematic view of the apparatus and ancillary equipment;

FIGURE 2 is a side elevational view of part of the apparatus;

FfGURE 3 is a front elevational view, partly in sec tion, of the apparatus; and,

FIGURE 4 is an enlarged diagrammatic view of the upper half of the apparatus in FIGURE 1, showing the path of travel of the upper work-roll.

Referring to FIGURE 1 of the drawings, a strip of metal 1, the thickness of which is to be reduced, is fed between a pair of feed rollers 52, 3 and through a heating chamber 4 and the heated metal is then fed between a pair of freely-rotatable work-rollers 5, 6 which act on opposite sides of the strip. The reduced strip passes between a pair of pinch rollers, 7, 8, another pair of guide rollers 9, it! and is Wound upon a coiling drum 11.

The freely-rotatable work-rollers are mounted on end portions of oppositely directed compound pendulums 12, 13. The compound pendulum 12 oscillates during operation of the apparatus by lever 14- which is connected to a driven crank 15. At the same time the compound pendulum 12 is caused to move upwardly towards the end of its oscillation from left to right by means of driven crank 16 (which is driven at the same speed as crank 15), lever 17, and bell crank lever 18 which is pivotally mounted on the upper framework 19 of the apparatus. Towards the end of its oscillation from right to left the compound pendulum is caused to move downwardly by the crank 116.

Similarly, the compound pendulum 13 is oscillated in synchronism with compound pendulum 12 by lever 20 which is connected to a driven crank 21 and is caused to move downwardly towards the end of its oscillation from left to right by means of driven crank 22 (which is driven in synchronism with the crank 21), lever 23, and bell crank lever 24 which is pivotally mounted on the lower framework 25 of the apparatus.

Thus, as the compound pendulums swing from left to right and the strip is fed continuously from right to left, the work-rollers 5 and 6, which are separated from each other at their point of nearest approach by a gap substantially equal to the thickness of the reduced strip when in the position shown in FIGURE 1, reduce the strip during that part of the swing when they contact the strip. During the return swing, that is to say from right to left, the work-rollers do not contact the strip by reason of the upward and downward movements of the compound pendulums 12 and 13.

FIGURE 4 shows the path of travel P of the upper 'roller 5, upper pendulum 12 and associated linkage being shown in solid lines in the extreme right position; and, in phantom lines in the extreme left position. The lower roller 6 traces a similar path P, by virtue of the identical linkage driving the lower pendulum 13.

In another embodiment of the invention the strip is reduced when the work-rolls are moving in the same direction as the movement of the strip.

Both these embodiment of the invention may be modified in that the strip is fed between the rolls intermittently, such feeding taking place when the metal is not undergoing any reduction.

Referring now to FIGURES 2 and 3, the apparatus comprises a framework having upper and lower portions 26, 27. The upper portion 26 has three upper bearings 28, 29 and 38 in which is rotatably-mounted a shaft 31, having eccentric portions 32 and 33. The eccentric portions 32 and 33 respectively carry bearings 34 and '35 of a compound pendulum formed by arms 36, 37,

38 and 39 joined together by a cross-piece The lower end portions of arms 36 and have bearings 41 and 42 in which a work-roller 43 is freely mounted for rotation. The Work roller is backed by three pairs of supporting rollers 44, 44, 45, 45 and -46, 46, which are freely mounted for rotation between arms 36 and 37, 3-7 and 3-8 and 38 and 39 respectively.

The compound pendulum is oscillated from left to right and back again by means of a lever 47 pivotallymounted at 48 at one end to the compound pendulum and pivotally-mounted at the other end to a crank 49 of a crankshaft 58. Rectilinear motion of the Workrollers away from and towards each other is effected by the shaft 31 which is oscillated by levers 51 and 52, the latter being pivotally-rnounted on crank 53 of crankshaft Sli The crankshaft is driven by any suitable driving means which is not shown in the drawings.

The lower portion 27 of the framework has a compound pendulum 54 (which is similar to the compound pendulum formed by arms 36, 37, 38 and 39 and crosspiece 40) mounted on an eccentric shaft 55, and having a work-roller 56. The compound pendulum is moved by lever 57 and crank 58 on a crankshaft 59 and by levers 60 and 61 and crank 62 on crankshaft 59. The crankshaft 59 is driven in synchronism by the driving means which drive the crankshaft 511.

Methods and apparatus in accordance with this invention are particularly suitable for reducing the thickness of titanium or its alloys but they are also suitable for reducing the thickness of other metals. or the metal to be reduced may be in the form of slab, plate or strip.

I claim:

1. Apparatus for reducing the thickness of metal comprising: a pair of oppositely directed swingable arms,

the free ends of which are adjacent; a freely rotatable Workroll mounted on the free end of each arm; first drive means connected to each arm to oscillate the same; and second drive means cooperatively operative with each The titanium said first drive means to cyclically move said workrolls toward and away from one another, said first and second drive means cooperating to cyclically move said workrolls in synchronism through a working stroke and an idle stroke, the path of the idle stroke for each workroll being outward of the path of the working stroke, the workrolls being rotated solely by engagement with the metal being wonked and a reduction of the metal thickness occurs during at least a portion of the movement through said working stroke.

2. Apparatus defined in claim 1 wherein said workrolls are mounted to said swim-gable arms at a fixed distance from the respective pivot axes thereof.

3. Apparatus for reducing the thickness of metal as claimed in claim 1 in which each work-roll is provided with at least two freely-rotatable backing trolls adjacent thereto to prevent bending of the workrolls.

4. Apparatus for reducing the thickness of metal comprising: a pair of oppositely directed swingable mms the free ends of which are adjacent; a freely rotatable work roll mounted on the free ends of each arm; a first oscillatory bell crank for each arm, said swingable arm being pivotally connected to one of said first bell cranks, a second rotatably driven bell crank mounted in laterally spaced relationship to said first bell crank; first drive means for oscillating said arm including a link pivotally connected to the other arm of said first bell crank and one arm of said second bell crank to thereby drive said swingable arm through said first bell crank upon rotation of said second bell crank; and second drive means cooperatively operative With each of said first drive means to cyclically move said work rolls towards and away from one another including a link pivotally connected to the other arm of said second bell crank and to said first swingable arm, said first and second drive means cooperating to cyclicall move said work rolls in synchronism through a working stroke and an idle stroke, the path of the idle stroke for each work roll being outwand of the path of the working stroke, the Work rolls being r0 tated solely by engagement with the metal being worked wherein a reduction of the metal thickness occurs during at least a portion of the movement through said working stroke.

References Cited in the file of this patent UNITED STATES PATENTS 9,471 Field Dec. 14, 1852 995,427 Inshaw June 13, 1911 1,513,565 Somersall Oct. 28, 1924 1,549,527 Fielding Aug. 11, 1925 1,908,267 McBain May 9, 1933 2,147,301 Krause Feb. 14, 1939 2,153,839 Libergeld Apr. 11, 1939 2,181,173 Catulle Nov. 28, 1939 2,271,459 McConnell Ian. 28, 1942 2,353,289 Bennewitz July 11, 1944 2,828,654 Ungerer Apr. 1, 1958 FOREIGN PATENTS 2,598 Great Britain Feb. 22, 1911 473,817 Great Britain Oct. 20, 1937 787,442 Great Britain Dec. '11, 1957 731,110 Great Britain June 1, 1955 704,757 Germany Apr. 5, 1941 

1. APPARATUS FOR REDUCING THE THICKNESS OF METAL COMPRISING: A PAIR OF OPPOSITELY DIRECTED SWINGABLE ARMS, THE FREE ENDS OF WHICH ARE ADJACENT; A FREELY ROTATABLE WORKROLL MOUNTED ON THE FREE END OF EACH ARM; FIRST DRIVE MEANS CONNECTED TO EACH ARM TO OSCILLATE THE SAME; AND SECOND DRIVE MEANS COOPERATIVELY OPERATIVE WITH EACH SAID FIRST DRIVE MEANS TO CYCLICALLY MOVE SAID WORKROLLS TOWARD AND AWAY FROM ONE ANOTHER, SAID FIRST AND SECOND DRIVE MEANS COOPERATING TO CYCLICALLY MOVE SAID WORKROLLS IN SYNCHRONISM THROUGH A WORKING STROKE AND AN IDLE STROKE, THE PATH OF THE IDLE STROKE FOR EACH WORKROLL BEING OUTWARD OF THE PATH OF THE WORKING STROKE, THE WORKROLLS BEING ROTATED SOLELY BY ENGAGEMENT WITH THE METAL BEING WORKED AND A REDUCTION OF THE METAL THICKNESS OCCURS DURING AT LEAST A PORTION OF THE MOVEMENT THROUGH SAID WORKING STROKE. 